Program recording medium, image processing apparatus, imaging apparatus, and image processing method

ABSTRACT

In a first step of a program, data of a plurality of still images generated by continuously imaging still images of a subject using an imaging apparatus is read into a calculating section. In a second step, the calculating section selects a specified image from among an object image group which includes the plurality of still images and in which respective images are continued in a time base direction. In a third step, the calculating section selects a first image to be added from images before the specified image in the time base direction among the object image group. Further, the calculating section determines an addition rate of the first image to be added to the specified image. In a fourth step, the calculating section records data of the addition rate of the first image to be added in association with data of the specified image.

CROSS REFERENCE TO THE RELATED APPLICATIONS

This application is a continuation application of InternationalApplication PCT/JP2008/001482, filed Jun. 10, 2008, designating theU.S., and claims the benefit of priority from Japanese PatentApplication No. 2007-199267, filed on Jul. 31, 2007, the entire contentsof which are incorporated herein by reference.

BACKGROUND

1. Field

The present application relates to an image processing technique tosmoothly display a plurality of still images as a motion image.

2. Description of the Related Art

Conventionally, an imaging apparatus capable of shooting a still imagewhile shooting a motion image is publicly known. For example, JapaneseUnexamined Patent Application Publication No. 2001-111934 discloses animaging apparatus that interpolates a missed motion image frame byshooting a still image.

Incidentally, preferred images differ between a still image and a motionimage in viewing. For example, in viewing a still image, a vivid imagewithout image deletion is preferred, however, in motion imagereproduction, an image with image deletion is preferred because motionis smoother. As a result, it has been comparatively difficult toreproduce both a motion image and a still image in a state preferablefor both, and therefore, its improvement is desired.

SUMMARY

A proposition of the present application, therefore, is to provide aunit that makes it possible to reproduce both a motion image and a stillimage in a state preferable for both.

An aspect of the present embodiment is a program of a computer having adata reading section that reads data of an image and a calculatingsection. The program causes the calculating section to execute thefollowing first step to fourth step. In the first step, the calculatingsection reads data of a plurality of still images generated bycontinuously imaging still images of a subject using an imagingapparatus. In the second step, the calculating section selects aspecified image from among an object image group which includes theplurality of still images and in which respective images are continuedin a time base direction. In the third step, the calculating sectionselects a first image to be added from images before the specified imagein the time base direction among the object image group in order togenerate a composite image by adding the first image to be added beforethe specified image in a time base direction to the specified image.Further, the calculating section determines an addition rate of thefirst image to be added to the specified image. In the fourth step, thecalculating section records data of the addition rate of the first imageto be added in association with data of the specified image.

Another aspect of the present embodiment is a program of a computerhaving a data reading section that reads data of an image and acalculating section. The program causes the calculating section toexecute the following first step to third step. In the first step, thecalculating section reads data of an object image group which includes aplurality of specified images and in which the respective images beingstill images continued in a time base direction, and addition rate datarecorded in correspondence with each of the specified images andindicative of an addition rate of images to be added to each of thespecified images, in case of generating composite images by adding atleast one or more images to be added, which are different in a time basedirection, to the specified image. In the second step, the calculatingsection generates a plurality of composite images by adding the imagesto be added to each of the specified images using the addition ratedata. In the third step, the calculating section reproduces and outputsthe plurality of composite images along time series.

Still another aspect of the present embodiment is a program of acomputer having a data reading section that reads data of an image, acalculating section, and a memory section. The program causes thecalculating section to execute the following first step to fourth step.In the first step, the calculating section reads data of a plurality ofstill images generated by continuously imaging still images of a subjectusing an imaging apparatus. In the second step, the calculating sectionselects specified images from among an object image group which includesthe plurality of still images and in which respective images arecontinued in a time base direction. In the third step, the calculatingsection generates composite images by adding at least one or more imagesto be added, which are different in a time base direction, to thespecified images based on addition rate data recorded in correspondencewith the specific images and indicative of an addition rate of theimages to be added to the specified images. Further, the calculatingsection generates data of a motion image from a plurality of compositeimages. In the fourth step, the calculating section records data of eachof the specified images along with the data of the motion image in thememory section.

Still another aspect of the present embodiment is a program of acomputer having a data reading section that reads data of an image, acalculating section, and an operation section. The program causes thecalculating section to execute the following first step to second step.In the first step, the calculating section reads respective data of aplurality of specified images being still images continued in a timebase direction, and data of a motion image. The data of theabove-mentioned motion image includes a plurality of composite imagesgenerated by adding an image, which is different in a time basedirection, to the specified images based on addition rate data recordedin correspondence with the specific images and indicative of an additionrate of the image, which is different in the time base direction, to thespecified images. In the second step, the calculating sectionselectively executes a first reproduction mode which reproduces andoutputs the specified images along time series and a second reproductionmode which reproduces and outputs the motion image.

What is converted and represented from the configuration according tothe above-mentioned embodiment into an image processing apparatus thatexecutes the above-mentioned programs, an imaging apparatus includingthe image processing apparatus, an image processing method, a recordingmedium storing the above-mentioned programs, etc., is also included inthe specific aspects of the present application.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram showing a configuration of an electroniccamera in a first embodiment.

FIG. 2 is a flowchart showing operations in a continuous shooting modein the first embodiment.

FIG. 3 is an explanatory diagram showing an example of a method ofdetermining a feature point in an interpolation image.

FIG. 4 is an explanatory diagram showing an example of a method ofdetermining a target pixel in an interpolation image.

FIGS. 5A and 5B are diagrams showing images constituting a compositeimage and an addition rate.

FIG. 6 is a flowchart showing operations in a reproduction mode in thefirst embodiment.

FIG. 7 is a diagram showing an example of a reproduction mode selectionscreen of an image file.

FIG. 8A is a diagram showing an example of a specified image.

FIG. 8B is a diagram schematically showing a composite image in whichFIG. 8A is a core of display.

FIG. 9 is a flowchart showing operations in a continuous shooting modein a second embodiment.

FIG. 10 is a flowchart showing operations in a reproduction mode in thesecond embodiment.

DETAILED DESCRIPTION OF THE EMBODIMENTS

<Explanation of First Embodiment>

FIG. 1 is a block diagram showing a configuration of an electroniccamera in a first embodiment. The electronic camera includes an imagingoptical system 11, a lens driving section 12, an image pickup device 13,an image pickup device driving circuit 14, a signal processing circuit15, a data processing circuit 16, a first memory 17, a display controlcircuit 18, a monitor 19, a compression/decompression circuit 20, arecording I/F (interface) 21, a communication I/F (interface) 22, anoperation member 23, a release button 24, a vibration sensor 25, asecond memory 26, a control circuit 27, and a bus 28.

Here, the data processing circuit 16, the first memory 17, thecompression/decompression circuit 20, the second memory 26, and thecontrol circuit 27 are coupled mutually via the bus 28, respectively.The lens driving section 12, the image pickup device driving circuit 14,the signal processing circuit 15, the display control circuit 18, therecording I/F 21, the communication I/F 22, the operation member 23, therelease button 24, and the vibration sensor 25 are coupled with thecontrol circuit 27, respectively (in FIG. 1, signal lines that couplethe signal processing circuit 15, the display control circuit 18, andthe control circuit 27 with each another are not shown schematically forthe sake of simplicity).

The imaging optical system 11 includes a plurality of lens groupsincluding a zoom lens and focusing lens and plays a role to form animage of a subject on the imaging plane of the image pickup device 13.For the sake of simplicity, in FIG. 1, the imaging optical system 11 isshown schematically as a single lens.

Each lens position of the imaging optical system 11 is adjusted in theoptical axis direction by the lens driving section 12. The lens drivingsection 12 includes a lens driving mechanism and adjusts the lensposition in accordance with a lens drive instruction from the controlcircuit 27. For example, by the lens driving section 12 driving thefocus lens back and forth in the optical axis direction, the focusadjustment of the imaging optical system 11 is made. Further, by thelens driving section 12 driving the zoom lens back and forth in theoptical axis direction, the zoom adjustment of the imaging opticalsystem 11 is made.

The image pickup device 13 photoelectrically converts a subject imageformed by light flux having passed through the imaging optical system 11and generates an analog image signal. The image pickup device 13 in thepresent embodiment is capable of imaging a single still image,continuously imaging still images, and imaging a motion image. Theoutput of the image pickup device 13 is coupled to the signal processingcircuit 15. The image pickup device 13 includes a CCD image sensor or aCMOS type image sensor.

The image pickup device driving circuit 14 generates a drive signal at apredetermined timing in response to an instruction from the controlcircuit 27 and supplies the drive signal to the image pickup device 13.Then, the image pickup device driving circuit 14 controls chargeaccumulation (imaging) and accumulated charge reading of the imagepickup device 13 by the above-mentioned drive signal.

The signal processing circuit 15 is an ASIC that performs various kindsof signal processing on the output of the image pickup device 13.Specifically, the signal processing circuit 15 performs correlationdouble sampling, gain adjustment, direct current reproduction, A/Dconversion, etc. Parameters of gain adjustment etc. in the signalprocessing circuit 15 are determined in accordance with an instructionfrom the control circuit 27. The signal processing circuit 15 is coupledto the data processing circuit 16 and the data after the above-mentionedsignal processing is output to the data processing circuit 16.

The data processing circuit 16 is a circuit that performs digital signalprocessing on the data of an image output from the signal processingcircuit 15. In the data processing circuit 16, image processing, such ascolor interpolation processing, gradation conversion processing, contourenhancement processing, and white balance adjustment, is performed. Thedata processing circuit 16 is coupled to the display control circuit 18and compression/decompression circuit 20, respectively. Then, the dataprocessing circuit 16 outputs the data of a recording image after imageprocessing to the compression/decompression circuit 20 in response to aninstruction from the control circuit 27.

Further, the data processing circuit 16 performs resolution conversion(pixel number conversion) processing of an image in response to aninstruction from the control circuit 27. As an example, when displayinga reproduction image on the monitor 19, the data processing circuit 16performs resolution conversion (pixel number conversion) processing onthe data of the image to be reproduced and displayed in order to matchthe data with the number of pixels of the monitor 19 (except whenspecified otherwise, when an image is displayed on the monitor 19 in thepresent specification, it is assumed that the adjustment of the numberof pixels of the image to be displayed has already been made in the dataprocessing circuit 16). Then, the data processing circuit 16 outputs thedata of the reproduction image after the resolution conversion to thedisplay control circuit 18. When performing electronic zoom processing,the data processing circuit 16 performs resolution conversion (pixelnumber conversion) processing on the data of the image to be input andoutputs the image data after the resolution conversion to thecompression/decompression circuit 20 and the display control circuit 18,respectively.

The first memory 17 is a buffer memory that temporarily stores imagedata in a process before or after the processing by the data processingcircuit 16 or the compression/decompression circuit 20.

The display control circuit 18 performs predetermined signal processing(for example, conversion of gradation characteristics in accordance withthe display characteristics of the monitor 19) on the image data inputfrom the data processing circuit 16 in response to an instruction fromthe control circuit 27 and outputs the data to the monitor 19. Thedisplay control circuit 18 performs processing to further superimposeoverlay image data of, such as a shooting menu and cursor, on theabove-mentioned image data. By such control by the control circuit 27and the display control circuit 18, it is possible to display a subjectimage superimposed with the overlay image on the monitor 19. The monitor19 in the present embodiment may include either an electronic finderhaving an ocular part or a liquid crystal display panel to be providedon the backside of a camera housing etc.

The compression/decompression circuit 20 performs predeterminedcompression processing on the image data input from the data processingcircuit 16 in response to an instruction from the control circuit 27.The compression/decompression circuit 20 is coupled to the recording I/F21 and the image data after the compression is output to the recordingI/F 21. Further, the compression/decompression circuit 20 performsdecoding processing, which is processing inverse to compressionprocessing, on the image data after the compression. Incidentally, thecompression/decompression circuit 20 in the present embodiment has aconfiguration capable of performing reversible compression (so-calledloss-less encoding).

In the recording I/F 21, a connector for coupling a memory medium 29 isformed. Then, the recording I/F 21 performs data write/read to/from thememory medium 29 coupled to the connector. The above-mentioned memorymedium 29 includes a compact hard disk, memory card that incorporates asemiconductor memory, and optical disk, such as DVD, etc. FIG. 1schematically shows a memory card as an example of the memory medium 29.The memory medium 29 may be one which is incorporated in an electroniccamera, or may be mounted to an electronic camera in anattachable/detachable manner. As a memory medium that reads and writesimage data, it may also be possible to utilize an external memory mediumelectrically coupled thereto via the communication I/F 22.

Here, when recording data of an image imaged in a shooting mode, whichis one of the operation modes of an electronic camera, the controlcircuit 27 displays a reproduction image corresponding to a recordingimage on the monitor 19. It is assumed that a recording image in thepresent specification means a still image obtained by imaging andcorresponding to still image data to be finally recorded in the memorymedium 29 (or already recorded in the memory medium 29).

When non-compression recording of a recording image is instructed to thecontrol circuit 27 by the operation of a user using the operation member23, the compression/decompression circuit 20 does not performcompression processing and outputs the data of the recording image tothe recording I/F 21. In the above-mentioned non-compression recordingalso, the control circuit 27 displays a reproduction image correspondingto the recording image on the monitor 19.

In the reproduction mode, which is one of the operation modes of theelectronic camera, the control circuit 27 displays the reproductionimage by the image data stored in the memory medium 29 on the monitor19. In the reproduction mode, the recording I/F 21 reads image data tobe reproduced from the memory medium 29 in response to an instructionfrom the control circuit 27. Then, after performing decoding processingon the image data to be reproduced, the compression/decompressioncircuit 20 sends the image data after the decoding to the dataprocessing circuit 16. Then, the data processing circuit 16 and displaycontrol circuit 18 perform the above-described processing on the imagedata after the decoding, and thereby, the reproduction image isdisplayed on the monitor 19. When non-compressed image data is read fromthe memory medium 29, the compression/decompression circuit 20 sends theimage data to the data processing circuit 16 without performing decodingprocessing.

The communication I/F 22 controls data transmission/reception with anexternal device 30 (for example, a personal computer or an externalmemory medium) in conformance to the specifications of thepublicly-known wired or wireless communication standards. Thecommunication between the electronic camera and the external device 30is established via a wired or wireless communication line.

The operation member 23 includes, for example, a command dial,cross-shaped cursor key, zoom operation button, determination button,etc. Then, the operation member 23 receives various inputs of theelectronic camera from a user. It may also be possible to provide asetting member to set a number of frames used to generate aninterpolation image, to be described later, to the operation member 23.

As an example, when receiving an input from the zoom operation button,the control circuit 27 outputs a lens drive instruction for the zoomlens and causes the lens driving section 12 to drive the zoom lens backand forth. Consequently, a subject image formed on the imaging plane ofthe image pickup device 13 is enlarged or reduced and thus, an opticalzoom adjustment by the imaging optical system 11 is made.

Further, when receiving an input from the zoom operation button, thecontrol circuit 27 outputs an instruction to the data processing circuit16 and varies the conversion rate of the resolution conversionprocessing for the image data in accordance with the operation of auser. Consequently, the image to be displayed on the monitor 19 isenlarged or reduced and an electronic zoom adjustment is made(electronic zoom). The conversion rate of the above-mentioned resolutionconversion processing corresponds to an electronic zoom magnification.When the data processing circuit 16 varies the conversion rate toincrease the electronic zoom magnification, part of the reproductionimage is displayed enlarged on the monitor 19 (as the enlargement ratioincreases, the display range of the reproduction image reduces). On theother hand, when the data processing circuit 16 varies the conversionrate to decrease the electronic zoom magnification, the enlargementratio of the reproduction image to be displayed on the monitor 19reduces, however, the display range of the reproduction image isenlarged. In the above-mentioned shooting mode, it is possible to recordthe data of an imaged image corresponding to the display image on themonitor 19 in the memory medium 29.

In the shooting mode, the release button 24 receives an input toinstruct the start of auto focus (AF) operation before shooting byhalf-pressing operation and an input to instruct the start of imagingoperation by fully-pressing operation.

The control circuit 27 performs the AF operation by the publicly-knowncontrast detection method in response to the half-pressing operation ofthe release button 24. In the AF operation, a signal corresponding to afocus detection region set in advance in the shooting screen is usedamong image signals read from the image pickup device 13. Specifically,the control circuit 27 sends a lens drive instruction of the focus lensto the lens driving section 12 so that the integrated value of highfrequency components (so-called focal point evaluation value) about thedata corresponding to the focus detection region is maximized amongimage data signal-processed by the signal processing circuit 15. Theposition of the focus lens where the focal point evaluation value ismaximized is an in-focus position where the blurring at the edge of asubject image imaged by the image pickup device 13 is eliminated and thecontrast of the image is maximized (the acutance is enhanced).

The vibration sensor 25 detects vibrations of the housing of theelectronic camera in two directions perpendicular to each other. Thevibration sensor 25 includes, for example, an angle speed sensor, a gyrosensor, etc., and is located in the housing of the electronic camera.The vibration sensor 25 detects vibrations applied to the electroniccamera in the shooting mode and outputs data of vibration amount in thetwo perpendicular directions to the control circuit 27. The controlcircuit 27 performs camera shake compensation based on theabove-mentioned data of vibration amount. For example, when the imagingoptical system 11 includes a camera shake compensation lens, the controlcircuit 27 performs camera shake compensation by driving the camerashake compensation lens via the lens driving section 12 so that themovement of a subject accompanying the vibrations of the housing iscanceled on the imaging plane.

The second memory 26 is a nonvolatile memory medium, such as a flashmemory. The second memory 26 stores various pieces of setting data.

The control circuit 27 is a processor that totally controls theoperation of the electronic camera. For example, the control circuit 27finds the brightness of the field from a signal output from the imagepickup device 13. Then, the control circuit 27 performs thepublicly-known AE operation based on the above-mentioned brightnessinformation and determines imaging conditions in the shooting mode(charge accumulation time of the image pickup device 13, the aperturevalue of the aperture (not shown schematically), degree of amplificationof an image signal).

Further, the control circuit 27 performs processing to generate aninterpolation image, composition processing by image addition in thetime direction, etc., by executing a program stored in the second memory26 etc. (the processing is described later).

Hereinafter, the operation in the continuous shooting mode and theoperation in the reproduction mode of the electronic camera in the firstembodiment are explained, respectively.

(Explanation of Continuous Shooting Mode)

FIG. 2 is a flowchart showing the operation in the continuous shootingmode in the first embodiment. Here, the continuous shooting mode is oneof the shooting modes described above, and in which the electroniccamera continuously performs the imaging operation of still images atpredetermined time intervals while the release button 24 is beingpressed. In the continuous shooting mode, the control circuit 27determines the imaging conditions so that each of the recording imagescontinuously shot is worth viewing. For example, the control circuit 27reduces the aperture to increase the depth of field.

Step S101: When detecting the pressing operation of the release button24, the control circuit 27 continuously performs the above-mentioned AFoperation and at the same time, performs the continuous shootingoperation of recording images.

Here, it may also be possible for the control circuit 27 to perform theAF operation in step S101 by tracking a specified subject that moves inthe screen. Alternatively, it may also be possible for the controlcircuit 27 to perform the AF operation so that an object at apredetermined shooting distance is always in focus. In S101, it may alsobe possible for the control circuit 27 to make a focus adjustment by themanual operation of a user via the operation member 23.

Further, as to the continuous shooting operation in S101, the controlcircuit 27 instructs the image pickup device driving circuit 14 tooutput a drive signal to perform the continuous shooting operation. Uponreceipt of the above-mentioned drive signal, the image pickup device 13outputs an image signal at a frame rate of, for example, 10 fps. Then,the image signal of each frame output from the image pickup device 13 issubjected to predetermined processing in the signal processing circuit15 and the data processing circuit 16. After that, the control circuit27 causes the first memory 17 to temporarily store the data of therecording image corresponding to each frame.

At the time of the continuous shooting operation, the data processingcircuit 16 performs resolution conversion processing on the data of therecording image and generates data of a view image in accordance withthe number of pixels of the monitor 19. Then, the data processingcircuit 16 sequentially supplies the view image data of each frame tothe monitor 19 via the display control circuit 18. At the time of thecontinuous shooting operation, by the control of the display controlcircuit 18, the view image corresponding to each frame is displayedsequentially on the monitor 19. Consequently, it is possible for a userto confirm the state of the field and the composition of the recordingimage by visually inspecting the view image on the monitor 19.

Step S102: The control circuit 27 performs feature point extractionprocessing on the data of each recording image (S101) stored in thefirst memory 17. Specifically, the control circuit 27 extracts edgecomponents of the data of the recording image and finds, for example,the position of the intersection (corner) of the extracted edges as afeature point. Then, the control circuit 27 records the position of thefeature point corresponding to the frame of each recording image in thefirst memory 17 or the second memory 26. The control circuit 27 mayextract a point specified by a user on the monitor 19 as a featurepoint.

Step S103: The control circuit 27 generates an interpolation image thatinterpolates frames of a plurality of recording images. The number ofpixels of the interpolation image is set to the same number of pixels ofthe recording image. Further, the control circuit 27 in the presentembodiment generates an interpolation image by performing a geometricmorphing process accompanied by deformation of the subject image or amorphing process in which the subject image does not deform but moves.

Specifically, the control circuit 27 generates an interpolation image bythe procedure shown by (a) to (g) below. Here, the number of frames ofthe interpolation image to be inserted between two recording images isvaried by the control circuit 27 in accordance with the input by a user.In the following example, for the sake of simplicity, a case isexplained, where interpolation images corresponding to two frames areinserted between the two recording images.

(a) The control circuit 27 specifies the frames of two recording imagesadjacent to each other in the time base direction as key frames.

(b) The control circuit 27 associates the feature points includedrespectively in the two key frames specified in (a) described above witheach another. For example, the control circuit 27 performs matchingprocessing of feature points between the two key frames and finds acorrespondence relationship between respective feature points.

(c) The control circuit 27 finds a function that couples the positionsof the pair of feature points associated with each other in (b)described above in the spatial direction (locus of the movement of thefeature points in the morphing operation). Here, the above-mentionedfunction may be one that couples the pair of feature points by astraight line, or one that couples the pair of feature points by aspline curve. The control circuit 27 finds the above-mentioned functionfor all of the feature points that can be associated between the two keyframes.

(d) The control circuit 27 determines the position of the feature pointin the frame of the interpolation image by the function obtained by (c)described above. Specifically, the control circuit 27 internally dividesthe section defined by the above-mentioned function and the pair offeature points in accordance with the number of inserted interpolationimages and specifies the internally divided position as the position ofthe feature point of the interpolation frame.

FIG. 3 is an explanatory diagram showing an example of a method ofdetermining a feature point in an interpolation image. In the example inFIG. 3, to feature points A, B, C in the first key frame, feature pointsD, E, F in the second key frame correspond, respectively. Then, thepositions of points (G, J) that internally divide the section into threeof the linear function that couples the first feature points A, D arethe positions of the first feature points in the respectiveinterpolation images. It is also possible to find the positions of thesecond feature points (H, K) and the positions of the third featurepoints (I, L) in the interpolation images by the same procedure as thatfor the above-mentioned first feature points.

(e) The control circuit 27 respectively finds the position of a targetpixel other than the feature points in the interpolation image.Specifically, the control circuit 27 defines the position of a targetpixel in the key frame by vectors that couple the feature points. Then,the control circuit 27 finds the position of the target pixel on theinterpolation image based on the definition of the above-mentionedvector.

FIG. 4 is an explanatory diagram showing an example of a method ofdetermining a target pixel in an interpolation image.

In the key frame that includes the feature points A, B, C and a targetpixel P, a vector {right arrow over (P)} that couples the feature pointA and the target pixel P can be defined as the following expression (1)of the relationship between a vector {right arrow over (X)} that couplesthe feature points A, B and a vector {right arrow over (Y)} that couplesthe feature points A, C.{right arrow over (P)}=a{right arrow over (X)}+b{right arrow over(Y)}  (1)Here, in the expression (1), a, b are coefficients.

On the other hand, in the interpolation image, when the positions offeature points A′, B′, C′ having a correspondence relationship with thefeature points A, B, C are already known, it is possible to find theposition of a target pixel P′ corresponding to the target pixel P in theinterpolation image as follows. That is, it is possible to obtain avector {right arrow over (P)}′ that couples the feature point A′ and thetarget pixel P′ by the following expression (2) of the relationshipbetween a vector {right arrow over (X)}′ that couples the feature pointsA′, B′ and a vector {right arrow over (Y)}′ that couples the featurepoints A′, C′.{right arrow over (P)}′=a{right arrow over (X)}′+b{right arrow over(Y)}′  (2)

Consequently, it is possible for the control circuit 27 to find theposition of each target pixel in the interpolation image by theabove-mentioned method.

(f) The control circuit 27 finds the change in gradation value of eachpixel in the interpolation image. Specifically, firstly, the controlcircuit 27 respectively finds the gradation values of the pixels (targetpixels) having a correspondence relationship between the two key frames.Secondly, the control circuit 27 internally divides the section of thetwo gradation values in accordance with the number of insertedinterpolation images and finds the gradation value of the target pixelin the interpolation image. As an example, when the gradation values ofthe target pixels in the two key frames are 130, 136, respectively, thecontrol circuit 27 finds points that internally divide the section ofthe gradation values 130 to 136 into three sections. Then, the controlcircuit 27 specifies the gradation values (132, 134) corresponding tothe above-mentioned internally divided points as gradation values of thetarget pixel in the respective interpolation images. The control circuit27 finds the above-mentioned gradation values for the values of RGB orYCbCr, respectively.

(g) The control circuit 27 records the interpolation image generated inthe above-mentioned processes in the first memory 17 or the secondmemory 26. Then, the control circuit 27 changes the key frames specifiedin (a) described above and repeats the processes from (b) to (g)described above. Consequently, the control circuit 27 generatesinterpolation images between all of the frames of the recording imagescontinuously shot, respectively.

Step S104: The control circuit 27 obtains a motion vector of a subjectbetween frames with the frames of two recording images neighboring inthe time base direction as an object. For example, the control circuit27 extracts a motion of the subject between frames in units of macroblocks of 16×16 pixels and obtains a motion vector of the subjectbetween frames from this result. In S104, the control circuit 27calculates the above-mentioned motion vectors respectively between allof the frames of the recording images continuously shot.

Step S105: The control circuit 27 finds a maximum value Z of themagnitude of a motion vector among the motion vectors (found in S104)between frames of each recording image. Then, the control circuit 27records the maximum value Z of the magnitude of the motion vector in thefirst memory 17.

Step S106: The control circuit 27 determines whether or not the maximumvalues Z of the magnitude of the motion vector (found in S105) are each“0” value between all of the frames. When the above-mentionedrequirement is met (YES side), the procedure moves to S115. On the otherhand, when the above-mentioned requirement is not met (NO side), theprocedure moves to S107. The situation when the determination result ison the YES side in S106 corresponds to a situation when a subject thebrightness and color of which change but which is motionless is shotcontinuously etc.

Step S107: The control circuit 27 selects one specified image from amongthe object image group including frames of recording images and framesof interpolation images. The specified image is an image used as thestandard when a composite image, to be described later, is generated.Most preferably, the specified image is selected from among the objectimage group so that the time intervals of the recording images and thoseof the interpolation images are equal when they are arranged in timeseries.

In S107 in the present embodiment, it is assumed that the controlcircuit 27 sequentially selects a specified image from among the framesof the recording images. In this selection, all of the specified imagesare selected from a plurality of recording images arranged in timeseries with none of mid-images being skipped.

Step S108: The control circuit 27 determines whether or not the currentspecified image selected in S107 is the first specified image (the firstrecording image by continuous shooting). When it is the first specifiedimage (YES side), the procedure moves to S113. On the other hand, whenit is not the first specified image (NO side), the procedure moves toS109.

Step S109: The control circuit 27 respectively reads valuescorresponding to those between the current specified image and the nextspecified image from the maximum values Z of the magnitude of the motionvector found in S105. Then, the control circuit 27 determines whether ornot the maximum value Z of the magnitude of the motion vector that isread is less than a threshold value Th (Z<Th). When the above-mentionedrequirement is met (YES side), the procedure moves to S110. On the otherhand, when the above-mentioned requirement is not met (NO side), theprocedure moves to S111.

Step S110: The control circuit 27 sets the number of frames to be addedwhen a composite image used in motion image reproduction is generated to“3” and at the same time, determines the addition rates of the specifiedimage and the interpolation image, respectively. A composite image is animage generated by adding an image different in the time base directionto a specified image to create the image deletion in the subject.

Specifically, the control circuit 27 selects interpolation images forone frame each before (past) and after (future) the specified image inthe time base direction (that is, a past interpolation imagecorresponding to one frame and a future interpolation imagecorresponding to one frame based on the specified image as a standard),respectively, as an image to be added. Then, the control circuit 27 setsthe addition rate of the specified image to 0.5. Further, the controlcircuit 27 sets the addition rate of each of the images to be added to0.25, respectively. That is, the addition rates of the images in S110are “0.25:0.5:0.25” when expressed in the time base direction (refer toFIG. 5A). After that, the control circuit 27 moves the procedure to theprocessing in S112.

Step S111: The control circuit 27 sets the number of frames to be addedwhen a composite image used in motion image reproduction is generated to“5” and at the same time, determines the addition rates of the specifiedimage and the interpolation image, respectively.

Specifically, the control circuit 27 selects interpolation imagescorresponding to two frames, respectively, before and after thespecified image in the time base direction (that is, past interpolationimages corresponding to up to two frames and future interpolation imagescorresponding to up to two frames based on the specified image as astandard), respectively, as an image to be added. Then, the controlcircuit 27 sets the addition rate of the specified image to 0.4.Further, the control circuit 27 sets the addition rate of theinterpolation image corresponding to the first frame before and afterthe specified image, as a standard, of the respective images to be addedto 0.2, respectively. Furthermore, the control circuit 27 sets theaddition rate of the interpolation image corresponding to the secondframe before and after the specified image, as a standard, of therespective images to be added to 0.1, respectively. That is, theaddition rates of the images in S111 are “0.1:0.2:0.4:0.2:0.1” whenexpressed in the time base direction (refer to FIG. 5B).

Step S112: The control circuit 27 temporarily stores the above-mentionednumber of added frames and the addition rate (found in S110 or S111) inassociation with the data of the specified image (S107) in the firstmemory 17.

Step S113: The control circuit 27 determines whether or notdetermination has been completed up to the frame second to the lastframe in the object image group including the frames of the recordingimages and the frames of the interpolation images. In the presentembodiment, whether or not determination has been completed up to theframe second to the last frame of the recording image is determined.When the above-mentioned requirement is met (YES side), the proceduremoves to S114. On the other hand, when the above-mentioned requirementis not met (NO side), the control circuit 27 returns the procedure toS107 and repeats the above-mentioned operations.

Step S114: The compression/decompression circuit 20 generates an imagefile by performing the Motion-JPEG compression in the state where thedata of the recording image and the data of the interpolation image arenot added (in the state where no composite image is generated) inresponse to an instruction of the control circuit 27. By the Motion-JPEGcompression, the recording capacity of the entire image data can bereduced. Then, the control circuit 27 records the number of added framesand the data of the addition rate in relation to each specified image inassociation within the image file. Further, the control circuit 27records a flag to the effect that the magnitude of the motion vector isnot “0” in the image file. Then, the image file is finally recorded inthe memory medium 29. After that, the control circuit 27 ends theprocessing in the continuous shooting mode.

As a result, when reproducing the image file in S114 as a motion image,the control circuit 27 can easily generate a composite image suitablefor motion image reproduction by referring to the number of added framesand the data of addition rate.

Step S115: The compression/decompression circuit 20 generates an imagefile by performing the Motion-JPEG compression in a state where the dataof recording image and the data of interpolation image are not added (ina state where no composite image is generated) in response to aninstruction of the control circuit 27. In S115, the control circuit 27records a flag to the effect that the magnitude of the motion vector is“0” in the image file. Then, the image file is finally recorded in thememory medium 29. The explanation of the flowchart in FIG. 2 iscompleted as above.

(Explanation of Reproduction Mode)

FIG. 6 is a flowchart showing operations in the reproduction mode in thefirst embodiment. The reproduction mode is explained on the assumptionthat the image file (generated in S114, S115) in the above-mentionedcontinuous shooting mode is an object of reproduction. The processing ofthe flowchart is started when a user issues an image reproductioninstruction by operating the operation member 23. That is, theprocessing of the flowchart is started when a user specifies “stillimage reproduction” or “motion image reproduction” shown in FIG. 7.

Step S201: The control circuit 27 determines whether or not still imagereproduction of an image file is instructed. When still imagereproduction is instructed (YES side), the procedure moves to S220. Onthe other hand, when still image reproduction is not instructed (NOside), the procedure moves to S202.

Step S202: The control circuit 27 reads an image file to be reproducedfrom the memory medium 29. Then, the compression/decompression circuit20 performs decoding processing on the image data in the image file inresponse to an instruction of the control circuit 27. The data of eachdecoded image is stored temporarily in the first memory 17.

Step S203: The control circuit 27 determines whether or not a flag tothe effect that the magnitude of the motion vector is “0” is recorded inthe image file to be reproduced. When the above-mentioned requirement ismet (YES side), the procedure moves to S213. The situation when thedetermination result is on the YES side in S203 corresponds to asituation when the object of reproduction is the image file in S115. Onthe other hand, when the above-mentioned requirement is not met (NOside), the procedure moves to S204. The situation when the determinationresult is on the NO side in S203 corresponds to a situation when theobject of reproduction is the image file in S114.

Step S204: The control circuit 27 displays a screen (refer to FIG. 7) onthe monitor 19, which screen prompts a user to select a reproductionmode of the image file between “normal movie reproduction” and “frame byframe reproduction (dynamic reproduction)”. Then, the control circuit 27waits for an input to select a reproduction mode from a user via theoperation member 23. Upon receipt of the above-mentioned input to selecta reproduction mode from the operation member 23, the control circuit 27moves the procedure to S205.

Step S205: The control circuit 27 determines whether or not the input toselect “normal movie reproduction” as a reproduction mode is made. When“normal movie reproduction” is selected (YES side), the procedure movesto S206. On the other hand, when “frame by frame reproduction” isselected (NO side), the procedure moves to S213.

Step S206: The control circuit 27 acquires the number of added framesand the data of addition rate in relation to each specified image fromthe image file to be reproduced. Then, the control circuit 27 generatesa composite image by adding the specified image and the interpolationimage based on the above-mentioned number of added frames and theaddition rate. Then, the control circuit 27 reproduces the specifiedimage of the first frame, the above-mentioned composite image, and thespecified image of the last frame on the monitor 19 as a motion imagealong time series via the data processing circuit 16 and the displaycontrol circuit 18. Thus, the motion image reproduction on the monitor19 is started.

FIG. 8A shows an example of a specified image. FIG. 8B schematicallyshows composite images having the specified image in FIG. 8A as a coreof display. In the example in FIG. 8B, the number of added frames is “5”and the addition rates of the images are “0.1:0.2:0.4:0.2:0.1” whenexpressed in the time base direction. In the composite image, pastimages and future images in the time base direction are added to thespecified image, which is a core of display, and therefore, the imagedeletion occurs on the screen. As a result, when a plurality ofcomposite images is viewed as a motion image, the image is preferablebecause the motion is smooth. The number of added frames and theaddition rate when a composite image is generated are varied by thecontrol circuit 27 in accordance with the magnitude of the motion framebetween the recording images continuously shot. As a result, in thepresent embodiment, it is possible to adjust the amount of imagedeletion of composite images to a preferable amount in accordance withthe motion of the subject in the shot scene.

Step S207: The control circuit 27 determines whether or not still imagedisplay (temporarily stop) is instructed from the operation member 23during the reproduction of motion image. When still image display(temporarily stop) is instructed (YES side), the procedure moves toS208. On the other hand, when not instructed (NO side), the proceduremoves to S212.

Step S208: The control circuit 27 temporarily stops motion imagereproduction. Then, the control circuit 27 reproduces and displays, as astill image on the monitor 19, the specified image included in thecomposite images being reproduced when still image display is instructedin the state where no addition is performed via the data processingcircuit 16 and the display control circuit 18.

That is, when still image display is instructed, the control circuit 27displays the specified image as it is, which is a core of display, onthe monitor 19 as a still image. This specified image has almost noimage deletion compared to the composite image, and therefore, it ispossible to reproduce a still image in the preferred state of fineappearance on the monitor 19.

Step S209: The control circuit 27 determines whether or not recordinginstruction of the still image during being reproduced and displayed isreceived from the operation member 23. When recording instruction isreceived (YES side), the procedure moves to S210. On the other hand,when not received (NO side), the procedure moves to S211.

Step S210: The control circuit 27 records identification data (marker)indicative of the specified image displayed as a still image in theimage file. After that, the control circuit 27 moves the procedure toS211.

Step S211: The control circuit 27 determines whether or not aninstruction to continue motion image reproduction is received from theoperation member 23. When an instruction to continue motion imagereproduction is received (YES side), the procedure moves to S212. On theother hand, when not received (NO side), the control circuit 27 ends theseries of processing.

Step S212: The control circuit 27 determines whether or not thespecified image in the last frame is reproduced. When theabove-mentioned requirement is met (YES side), the control circuit 27ends the series of processing as well as ending the reproduction of theimage file. On the other hand, when the above-mentioned requirement isnot met (NO side), the control circuit 27 returns the procedure to S206and repeats the above-mentioned operations.

Step S213: The control circuit 27 continuously reproduces only therecording images of the decoded images in a frame by frame reproductionmanner on the monitor 19 along time series via the data processingcircuit 16 and the display control circuit 18 (dynamic reproduction).Consequently, the dynamic reproduction of the recording images obtainedby continuous shooting is started. In this case, the control circuit 27may also continuously reproduce the interpolation images and therecording images along time series.

Step S214: The control circuit 27 determines whether or not aninstruction to display a still image is received from the operationmember 23 during dynamic reproduction. When an instruction to display astill image is received (YES side), the procedure moves to S215. On theother hand, when not received (NO side), the procedure moves to S219.

Step S215: The control circuit 27 temporarily stops dynamic reproductionand displays the image being reproduced when still image display isinstructed on the monitor 19 as a still image.

Step S216: The control circuit 27 determines whether or not a recordinginstruction to record the still image (S215) during being reproduced anddisplayed is received from the operation member 23. When the recordinginstruction is received (YES side), the procedure moves to S217. On theother hand, when not received (NO side), the procedure moves to S218.

Step S217: The control circuit 27 records identification data (marker)indicative of the image displayed as a still image in the image file.After that, the control circuit 27 moves the procedure to S218.

Step S218: The control circuit 27 determines whether or not aninstruction to continue dynamic reproduction is received from theoperation member 23. When an instruction to continue dynamicreproduction is received (YES side), the procedure moves to S219. On theother hand, when not received (NO side), the control circuit 27 ends aseries of processing.

Step S219: The control circuit 27 determines whether or not the image inthe final frame of the image file is reproduced. When theabove-mentioned requirement is met (YES side), the control circuit 27ends a series of processing as well as ending the reproduction of theimage file. On the other hand, when the above-mentioned requirement isnot met (NO side), the control circuit 27 returns the procedure to S213and repeats the above-mentioned operations.

Step S220: The control circuit 27 displays the image in the image fileon the monitor 19 as a still image via the data processing circuit 16and the display control circuit 18. When the identification data(generated in S210, S217) is included in the image file, the controlcircuit 27 can extract the image corresponding to the identificationdata and quickly reproduce and display the image on the monitor 19. Theexplanation of the flowchart in FIG. 6 is completed as above.

Hereinafter, the working and effect of the first embodiment aredescribed. The electronic camera in the first embodiment, in order togenerate a composite image, records the addition rate of the image to beadded in association with the specified image. Then, the electroniccamera adds the interpolation images before and after the specifiedimage in the time base direction based on the addition rate andgenerates a composition image having the image deletion to performmotion image reproduction. As a result, in the first embodiment, whenreproducing the recording images obtained by continuous shooting as amotion image, it is possible to reproduce a motion image in which theflow of motions is smooth and preferred on the monitor 19.

Further, the electronic camera in the first embodiment displays thespecified image, which is a core of display, on the monitor 19 as astill image when an instruction to reproduce a still image is issuedduring reproduction of a motion image. As a result, in the firstembodiment, it is possible to reproduce a still image in the preferredstate where there is no image deletion on the monitor 19 when displayingone frame as a still image during reproduction of a motion image.

Further, with the electronic camera in the first embodiment, it ispossible to reduce the recording capacity compared to when both themotion image file including the composite images and the data of aplurality of specified images are recorded.

<Explanation of Second Embodiment>

Hereinafter, the operation in a continuous shooting mode and theoperation in a reproduction mode of an electronic camera in a secondembodiment are explained, respectively. Here, the second embodiment is amodified example of the first embodiment. The configuration of theelectronic camera in the second embodiment is common to that of theelectronic camera in the first embodiment shown in FIG. 1, andtherefore, its duplicated explanation is omitted.

(Explanation of Continuous Shooting Mode)

FIG. 9 is a flowchart showing the operation in the continuous shootingmode in the second embodiment. S301 to S311 in FIG. 9 correspond to S101to S111 in FIG. 2, respectively. S315 in FIG. 9 corresponds to S115 inFIG. 2. Accordingly, duplicated explanation of each step is omitted.

Step S312: The control circuit 27 generates a composite image by addingthe data of specified image and the interpolation image based on theabove-mentioned number of added frames and the addition rate (obtainedin S110 or S111). Then, the control circuit 27 temporarily stores thedata of the generated composite image in the first memory 17.

Step S313: The control circuit 27 determines whether or notdetermination of the frames up to the frame second to the last frame inthe object image group including the frame of the recording image andthe frame of the interpolation image is completed. In the presentembodiment, whether or not determination of the frames up to the framesecond to the last frame of the recording image is completed isdetermined. When the above-mentioned requirement is met (YES side), theprocedure moves to S314. On the other hand, when the above-mentionedrequirement is not met (NO side), the control circuit 27 returns theprocedure to S307 and repeats the above-mentioned operations.

Step S314: The compression/decompression circuit 20 generates a firstimage file by performing the Motion-JPEG compression in a state wherethe data of the recording image and the data of the interpolation imageare not added (in a state where no composite image is generated) inresponse to an instruction of the control circuit 27.

Further, the compression/decompression circuit 20 generates a secondimage file by performing the MPEG compression using the specified imagein the first frame, the above-mentioned composite image, and thespecified image in the final frame as a single motion image in responseto the instruction of the control circuit 27.

The control circuit 27 records a flag to the effect that the magnitudeof the motion vector is not “0” in the first image file and the secondimage file, respectively. Then, the first image file and the secondimage file are finally stored in the memory medium 29. After that, thecontrol circuit 27 ends the processing of the continuous shooting mode.The explanation of the flowchart in FIG. 9 is completed as above.

(Explanation of Reproduction Mode)

FIG. 10 is a flowchart showing the operation in the reproduction mode inthe second embodiment. The reproduction mode is explained on theassumption that the image file generated in the above-mentioned S314 isthe object for reproduction among those in the above-mentionedcontinuous shooting mode. The processing of the flowchart is startedwhen a user issues an image reproduction instruction by operating theoperation member 23. That is, the processing of the flowchart is startedwhen “still image reproduction” or “motion image reproduction” shown inFIG. 7 is instructed.

Step S401: The control circuit 27 determines whether or not still imagereproduction of an image file is instructed. When still imagereproduction is instructed (YES side), the procedure moves to S418. Onthe other hand, when not instructed (NO side), the procedure moves toS402.

Step S402: The control circuit 27 displays a screen (refer to FIG. 7) onthe monitor 19, which prompts a user to select a reproduction mode ofthe image file between “normal movie reproduction” and “frame by framereproduction (dynamic reproduction)”. Then, the control circuit 27 waitsfor an input to select a reproduction mode from a user via the operationmember 23. Upon receipt of the above-mentioned input to select areproduction mode from the operation member 23, the control circuit 27moves the procedure to S403.

Step S403: The control circuit 27 determines whether or not the input toselect the reproduction mode of “normal movie reproduction” is made.When “normal movie reproduction” is selected (YES side), the proceduremoves to S404. On the other hand, when “frame by frame reproduction” isselected (NO side), the procedure moves to S407.

Step S404: The control circuit 27 reads the second image file of theimage files to be reproduced from the memory medium 29. Then, thecompression/decompression circuit 20 performs the decoding processing ofthe image data in the second image file in response to an instruction ofthe control circuit 27. The data of each decoded image is storedtemporarily in the first memory 17.

Step S405: The control circuit 27 reproduces the image data (thespecified image in the first frame, the composite image, the specifiedimage in the last frame) buffered in the first memory 17 as a motionimage along time series on the monitor 19 via the data processingcircuit 16 and the display control circuit 18.

Step S406: The control circuit 27 determines whether or not thespecified image in the final frame is reproduced. When theabove-mentioned requirement is met (YES side), the control circuit 27ends the series of processing as well as ending reproduction of theimage file. On the other hand, when the above-mentioned requirement isnot met (NO side), the control circuit 27 returns the procedure to S405and repeats the above-mentioned operations.

Step S407: The control circuit 27 reads the first image file of theimage files to be reproduced from the memory medium 29. Then, thecompression/decompression circuit 20 performs decoding processing on theimage data in the first image file in response to an instruction of thecontrol circuit 27. The data of each decoded image is stored temporarilyin the first memory 17.

Step S408: The control circuit 27 continuously reproduces only therecording images of the image data buffered in the first memory 17 onthe monitor 19 in a frame by frame reproduction manner (dynamicreproduction) along time series via the data processing circuit 16 andthe display control circuit 18. In this case, the control circuit 27 mayalso continuously reproduce the interpolation images and the recordingimages along time series.

Step S409: The control circuit 27 determines whether or not aninstruction to display a still image is received from the operationmember 23 during dynamic reproduction. When an instruction to display astill image is received (YES side), the procedure moves to S410. On theother hand, when not received (NO side), the procedure moves to stepS414.

Step S410: The control circuit 27 temporarily stops dynamic reproductionand displays the image being reproduced when still image display isinstructed on the monitor 19 as a still image.

Step S411: The control circuit 27 determines whether or not a preserveinstruction of the still image (S411) during being reproduced anddisplayed is received from the operation member 23. When preservationinstruction is received (YES side), the procedure moves to S412. On theother hand, when not received (NO side), the procedure moves to S413.

Step S412: The control circuit 27 records identification data (marker)indicative of the image displayed as a still image in the first imagefile.

Step S413: The control circuit 27 determines whether or not aninstruction to continue dynamic reproduction is received from theoperation member 23. When an instruction to continue dynamicreproduction is received (YES side), the procedure moves to S414. On theother hand, when not received (NO side), the procedure moves to S415.

Step S414: The control circuit 27 determines whether or not the image inthe final frame of the first image file is reproduced. When theabove-mentioned requirement is met (YES side), the control circuit 27moves the procedure to S415 as well as ending the reproduction of theimage file. On the other hand, when the above-mentioned requirement isnot met (NO side), the control circuit 27 returns the procedure to S408and repeats the above-mentioned operations.

Step S415: The control circuit 27 displays a confirmation screen (notshown schematically) on the monitor 19, which prompts a user to confirmthe erasure of images not associated with the identification data(images other than those displayed as still images) of the image data ofthe first image file when the first image file includes theidentification data (generated in S412). Then, the control circuit 27waits for an input from the user via the operation member 23.

Step S416: The control circuit 27 determines whether or not an input topermit image erasure is received from the operation member 23. Whenimage erasure permission is input (YES side), the procedure moves toS417. On the other hand, when image erasure cancellation is input (NOside), the control circuit 27 ends the series of the processing. In thiscase, the first image file is preserved as it is.

Step S417: The control circuit 27 erases as a whole all the image data(data of the recording images and the interpolation images) other thanthose associated with the identification data of the image data of thefirst image file. Consequently, it is possible to reduce the data sizeof the first image file while reserving the still images selected by theuser. After that, the control circuit 27 ends the series of theprocessing.

Step S418: The control circuit 27 displays an image in the image file onthe monitor 19 as a still image via the data processing circuit 16 andthe display control circuit 18. The explanation of the flowchart in FIG.10 is completed as above.

The electronic camera in the second embodiment records the motion imagedata of the composite image generated by adding the image to be added tothe specified image (second image file) and the data of each specifiedimage (first image file). As a result, the electronic camera in thesecond embodiment can easily reproduce the specified image suitable forstill image display and the composite image suitable for motion imagedisplay.

(Supplementary Items of Embodiments)

(1) In the electronic camera in the above-mentioned embodiments, it mayalso be possible to locate a phase difference AF module in a shootinglight path and to perform a phase difference AF operation by thepublicly known pupil division in addition to the contrast AF operation.Further, in the above-mentioned embodiments, the example is explained,in which the AE calculation is performed based on the output of theimage pickup device 13, however, it may also be possible to provide aphotometric element for AE calculation separately from the image pickupdevice 13.

(2) In the above-mentioned embodiments, the example is explained, inwhich the interpolation image and the composite image are generated fromthe data of the recording image. However, in the above-mentionedembodiments, for example, when the data of the recording image and thedata of the view image set to the display size of the monitor 19 or lessare grouped and recorded in the memory medium 29, the control circuit 27may generate the interpolation image and the composite image from thedata of the view image by preferentially selecting the data of theabove-mentioned view image.

(3) In the above-mentioned embodiments, the motion vector is obtainedbetween two recording images, however, it may also be possible to obtaina motion vector between a recording image and an interpolation image.

(4) In the above-mentioned embodiments, the example is explained, inwhich the specified image is selected from the recording imagescontinuously shot, however, it may also be possible to select thespecified image from the frame of the interpolation image and generate acomposite image by adding images before and after the interpolationimage in the time base direction as images to be added.

(5) The compression method of an image file in the first embodiment isnot limited to the Motion-JPEG compression and another compressionmethod, such as a codec of movie lossless compression and a method inwhich compression in the time base direction is not performed(Motion-JPEG 2000 etc.) may be accepted. Alternatively, in the firstembodiment, it may also be possible to generate an image file bycompression processing in conformance with the MPEG standards.

Further, also in the second embodiment, it may be possible to compressthe first image file in conformance with the MPEG standards or to recordthe second image file in a compression method, such as Motion-JPEG.

(6) In the reproduction mode in the above-mentioned second embodiment,the control circuit 27 may generate identification data indicative ofthe specified image corresponding to the composite image at the time ofreproduction stop when receiving the instruction to stop thereproduction of the motion image from the operation section during thereproduction of the second image file. Then, the control circuit 27 mayerase the data of all the images (data of the recording images and theinterpolation images) other than those corresponding to theidentification data of the first image file as above-mentioned S415 toS417.

(7) In the above-mentioned embodiments, the example is explained, inwhich the control circuit 27 of the electronic camera generates thecomposite image etc., however, for example, the external device 30(personal computer etc.) coupled with the electronic camera may performthe processing of the control circuit 27 in the above-mentionedembodiments. Further, it may also be possible to realize the algorithmexplained in the above-mentioned first embodiment or the secondembodiment by causing the external device 30 to share part of theprocessing to be performed by the control circuit 27 of the electroniccamera in the above-mentioned embodiments so that the electronic cameraand the external device 30 cooperate.

(8) In the above-mentioned embodiments, the example is explained, inwhich the composite image is generated by selecting images to be addedfrom the images before and after the specified image with respect totime. However, in the above-mentioned embodiments, it may also bepossible to select an image to be added only from the image before thespecified image with respect to time (or only from the image after thespecified image with respect to time).

(9) In S112 in the above-mentioned embodiments, the configuration isexplained, in which the data of the number of added frames and theaddition rate are associated only with the data of the specified imageand recorded. However, in the above-mentioned embodiments, it may alsobe possible to associate the data of each image in the object imagegroup with the data indicative of the specified when an image iscomposited and the data of the addition rate at the time of imagecomposition, respectively, and record the data.

Hereinafter, the above-mentioned example is explained specifically byreferring to FIG. 5B. In this example, the number of added frames is setto “5” and the addition rates expressed in the time base direction areassumed to be “0.1:0.2:0.4:0.2:0.1”. For example, when the centralrecording image in the object image group shown in FIG. 5B is thespecified image, the data indicative of the “central recording image” asthe specified image and the addition rate “0.1” at that time areassociated with the data of the second image (interpolation image) fromthe right and recorded. Similarly, when the rightmost recording image isthe specified image, the data indicative of the “right recording image”as the specified image and the addition rate “0.2” at that time areassociated with the data of the second image (interpolation image) fromthe right and recorded.

(10) In the processing in S101, S301 in the above-mentioned embodiments,the example is explained, in which the data of the recording image isrecorded in the first memory 17, however, it may also be possible torecord the data of the recording image in the memory medium 29 in theabove-mentioned case. In this case, the processing after S102, S302 isperformed based on the data of the recording image stored in the memorymedium 29 as a result.

(11) In the continuous shooting mode in the above-mentioned embodiments,when the specified image is selected from both the recording image andthe interpolation image, or when the specified image is selected frompart of the recording image, the control circuit 27 finds a maximumvalue Z′ of the motion vector from the current specified image and thenext specified image. Then, it is assumed that the control circuit 27 inthis case performs the determination of Z′<Th in S109, S309.

The many features and advantages of the embodiments are apparent fromthe detailed specification and, thus, it is intended by the appendedclaims to cover all such features and advantages of the embodiments thatfall within the true spirit and scope thereof. Further, since numerousmodifications and changes will readily occur to those skilled in theart, it is not desired to limit the inventive embodiments to the exactconstruction and operation illustrated and described, and accordinglyall suitable modifications and equivalents may be resorted to, fallingwithin the scope thereof.

What is claimed is:
 1. A non-transitory computer readable programrecording medium storing, for a computer having a data reading sectionwhich reads data of an image and having a calculating section, a programto cause the calculating section to execute: a first step reading, intothe calculating section, data of a plurality of still images generatedby continuously imaging still images of a subject using an imagingapparatus; a second step generating an interpolation image byinterpolating change in position of the subject between two images ofthe plurality of still images; a third step determining a specifiedimage from among an object image group which includes the plurality ofstill images and the interpolation image, respective images in theobject image group being continued in a time base direction; a fourthstep determining a first image to be added from images among the objectimage group before the specified image in the time base direction andwith different positions of the subject in order to generate a compositeimage by adding the first image to be added before the specified imagein the time base direction to the specified image and determining anaddition rate of the first image to be added to the specified image; anda fifth step recording data of the first image to be added and theaddition rate in correspondence with data of the respective images inthe object image group in association with the data of the respectiveimages.
 2. The non-transitory computer readable program recoding mediumaccording to claim 1, storing a program to cause the calculating sectionto further execute: a sixth step selecting a second image to be addedfrom an image after the specified image among the object image group inorder to generate a composite image by adding the image after thespecified image in the time base direction to the specified image anddetermining an addition rate of the second image to be added to thespecified image; and a seventh step recording data of the addition rateof the second image to be added in association with data of thespecified image.
 3. The non-transitory computer readable programrecording medium according to claim 1, storing a program to cause thecalculating section in at least one of the steps to perform functionsof: obtaining a motion vector of the subject between a standard imageand the specified image by using the standard image which is differentin the time base direction with respect to the specified image among theobject image group; and varying an addition rate of an image to be addedto the specified image in accordance with a magnitude of the motionvector.
 4. The non-transitory computer readable program recording mediumaccording to claim 1, storing a program wherein: the computer furtherhas a monitor; and an image size of the specified image is set to be adisplay size or less of the monitor.
 5. An image processing apparatuscomprising the computer executing the program stored in thenon-transitory program recording medium according to claim
 1. 6. Animaging apparatus comprising: an imaging section imaging a subject togenerate data of an imaged image; and the image processing apparatusaccording to claim
 5. 7. The non-transitory computer readable programrecoding medium according to claim 1, wherein the specified image isselected from among the plurality of still images.
 8. A non-transitorycomputer readable program recording medium storing, for a computerhaving a data reading section which reads data of an image, acalculating section, and an operating section, a program comprising: afirst step reading, into the calculating section, data of an objectimage group which includes a plurality of specified images andinterpolation images having each been generated by interpolating imagesof the object image group, respective images in the object image groupbeing still images continued in a time base direction, and readingaddition rate data recorded in correspondence with each of the specifiedimages and indicative of an addition rate of images to be added to eachof the specified images, in case of generating composite images byadding at least one or more images to be added to the specified images,the images to be added being different in the time base direction; asecond step generating a plurality of the composite images using dataindicative of a specified image at a time of compositing the image andaddition rate data at the time of compositing the image; a third stepreproducing and outputting the plurality of the composite images alongtime series; and a fourth step displaying and outputting, as a stillimage, the specified image, which is an image used for generating thecomposite images being reproduced, when receiving an instruction totemporarily stop from the operating section during the reproduction andoutput in the third step.
 9. The non-transitory computer readableprogram recording medium according to claim 8, storing a programwherein: the computer further has an operation section; a firstreproduction mode which executes the second step and the third step, anda second reproduction mode are provided; and in the second reproductionmode, the calculating section reproduces and outputs the specifiedimages along time series and displays and outputs, as a still image, aspecified image being reproduced when receiving an instruction totemporarily stop from the operation section during the reproduction andoutput.
 10. The non-transitory computer readable program recordingmedium according to claim 8, storing a program to cause the calculatingsection to further execute a fifth step generating identification dataindicative of the specified image displayed and output as the stillimage.
 11. The non-transitory computer readable program recording mediumaccording to claim 8, storing a program wherein: the computer furtherhas a monitor, and data of each of the specified images in the objectimage group is made up by grouping data of a plurality of images havingthe same composition but image sizes being different; and thecalculating section generates the composite images preferentially usingimages with the image sizes equal to or less than a display size of themonitor from among the data of the specified images in the second step.12. An image processing apparatus comprising the computer executing theprogram stored in the non-transitory program recording medium accordingto claim
 8. 13. An imaging apparatus comprising: an imaging sectionimaging a subject to generate data of an imaged image; and the imageprocessing apparatus according to claim
 12. 14. A non-transitorycomputer readable program recording medium storing, for a computerhaving a data reading section which reads data of an image, acalculating section, and an operation section, a program to cause thecalculating section to execute: a first step reading, into thecalculating section, respective data of a plurality of specified imagesbeing still images continued in a time base direction, and data of amotion image including a plurality of composite images generated byadding an image to the specified images based on addition rate datarecorded in correspondence with the specified images and indicative ofan addition rate of the image to the specified images, the image beingdifferent in the time base direction; a second step selectivelyexecuting a first reproduction mode which reproduces and outputs thespecified images along time series and a second reproduction mode whichreproduces and outputs the motion image in response to an input from theoperation section; a third step generating first identification dataindicative of a specified image being reproduced when receiving a timeseries reproduction stop instruction to stop reproduction of thespecified images along the time series from the operation section in astate where the first reproduction mode is selected in the second step;a fourth step generating second identification data indicative of thespecified image in correspondence with a composite image being displayedwhen receiving an instruction to stop reproduction of the motion imagefrom the operation section in a state where the second reproduction modeis selected in the second step; and a fifth step erasing data of all thespecified images except the specified images corresponding to one of thefirst identification data and the second identification data.
 15. Animage processing method using one or more computers, comprising: a firststep reading, into the one or more computers, data of a plurality ofstill images generated by continuously imaging still images of a subjectusing an imaging apparatus; a second step, by the one or more computers,generating an interpolation image by interpolating change in position ofthe subject between two images of the plurality of still images; a thirdstep, by the one or more computers, determining a specified image fromamong an object image group which includes the plurality of still imagesand the interpolation image, respective images in the object image groupbeing continued in a time base direction; a fourth step, by the one ormore computers, determining a first image to be added from images amongthe object image group before the specified image and with differentpositions of the subject in order to generate a composite image byadding the first image to be added before the specified image in a timebase direction to the specified image, and, by the one or morecomputers, determining an addition rate of the first image to be addedto the specified image; and a fifth step, in the one or more computers,recording data of the first image to be added and the addition rate incorrespondence with data of the respective images in the object imagegroup in association with the data of the respective images.
 16. Theimage processing method according to claim 15, wherein the specifiedimage is selected from among the plurality of still images.
 17. An imageprocessing method using one or more computers, comprising: a first stepreading, into the one or more computers, data of an object image groupwhich includes a plurality of specified images and interpolation imageshaving each been generated by interpolating images of the object imagegroup, respective images in the object image group being still imagescontinued in a time base direction, and reading addition rate datarecorded in correspondence with each of the specified images andindicative of an addition rate of images to be added to each of thespecified images when generating composite images by adding at least oneor more images to be added to the specified images, the images to beadded being different in the time base direction; a second step, by theone or more computers, generating a plurality of the composite imagesusing data indicative of a specified image at a time of compositing theimage and addition rate data at the time of compositing the image; athird step, by the one or more computers, reproducing and outputting theplurality of the composite images along time series; and a fourth step,by the one or more computers, displaying and outputting as a stillimage, the specified image, which is an image used for generating thecomposite images being reproduced, when receiving an instruction totemporarily stop during the reproduction and output in the third step.